Deletion 5q35 syndrome

What it is

Deletion 5q35 refers to the different congenital malformation syndromes resulting from deletions of variable extent of the terminal part of the long arm of chromosome 5 (5q), spanning the region from 5q35.1 to 5q35.3 . The most significant anomaly is a recurring deletion in 5q35.2 comprising the NSD1 gene that causes Sotos syndrome that is characterized by cardinal features including excessive growth during childhood, macrocephaly, distinctive facial gestalt and various degrees of learning difficulty. Subtelomeric deletions of the terminal 3.5 Mb region on 5q35.3 are very rare, characterized by prenatal lymphedema with increased nuchal translucency, pronounced muscular hypotonia in infancy, borderline intelligence, postnatal short stature due to growth hormone deficiency, and a variety of minor anomalies such as mildly bell-shaped chest, minor congenital heart defects and a distinct facial gestalt. Larger deletions including bands 5q35.1, 5q35.2 and 5q35.3 cause a more severe phenotype that associates severe developmental delay with microcephaly, and significant cardiac defects (e.g. atrial septal defect with/without atrioventricular conduction defects, Ebstein anomaly, tetralogy of Fallot) linked to haploinsufficiency of NKX2.5 (5q35.1). Various combinations of signs may result from deletions of variable extent depending on the genes comprised in the deleted segment.

Key facts

Prevalence

<1 / 1 000 000

Age of onset

Antenatal, Neonatal

Inheritance

Not applicable, Unknown

Classified as

Malformation syndrome

Prevalence figures describe populations, not individuals, and are often estimates from a single study. Where the figure is an incidence or a birth prevalence, it says so.

Signs and symptoms

These ranges are how often a sign appears across everyone diagnosed, not a prediction for one person — most people have some of these and not others. Orphanet also records findings that are specifically absent in this disease; those are in the data but not listed here.

Genes

ICD-10 codes

ICD-10 has no distinct code for most rare diseases, so many are filed under the nearest available one. A shared code identifies the group, not this disease — the ORPHAcode above is what identifies it.

Related health topics

Reached through the ICD-10 categories this disease is filed under, so these describe the broader group rather than this disease specifically.

Cross-references